Letter Grade Calculator

How to use this letter grade calculator

The tool has two tabs and one shared grading scale.

Convert works in both directions at once. Type a score in the left box to get its letter, or pick a letter on the right to get the score range that letter covers. Whichever box you touch, the other one answers. Scores can be a percent like 87, or points like 43/50, and the tool works out the percent for you.

Average letters is for when your grades arrived as letters rather than numbers. Add a row per course, pick the letter, and put its credit value in the last column. Leave Weight by credits ticked and a four-credit course counts four times as heavily as a one-credit one. Untick it and every course counts the same.

Under both tabs sits Your grading scale, and it is the part most people need and few calculators offer. Every letter has a tick box, a cutoff and a points value. Untick a letter your school does not award. Change a cutoff that does not match your handbook. The rest of the page updates around whatever you set.

What letter grade is my score?

A number grade becomes a letter by finding the highest cutoff it reaches. On the standard plus and minus scale this page starts with, 87% reaches the B+ cutoff of 87 but not the A- cutoff of 90, so it is a B plus. The tool shows that reasoning under the answer rather than just handing you a letter.

A few that people look up constantly, on that same scale:

• 78% is a C plus. The band runs 77 to 79.99.
• 85% is a B. The band runs 83 to 86.99.
• 90% is an A minus, and only just. One point lower is a B plus.
• 93% is a straight A.

Points work the same way once they are a percent. Enter 43/50 and the tool divides first, gets 86%, and returns a B. If turning points into a percentage is all you need, the grade percentage calculator does that one step on its own. If your score comes in above 100 because of extra credit, it still lands on the top band and the tool says so rather than pretending 105% is ordinary.

The boundaries are where this gets interesting, and where the scale editor earns its place. An 89.99 and a 90 are a hundredth of a point apart and two different letters. That is not a quirk of this calculator, it is how cutoffs work everywhere, which is why it matters that the cutoffs are yours and not ours.

Going the other way: what percentage is a B plus?

This direction is not the mirror image of the first, and almost nothing online admits it.

A score converts to exactly one letter. A letter converts back to a range. A B plus is not 88%. A B plus is anything from 87 to 89.99, and the student who scraped an 87 and the student who nearly reached 90 both carry the same letter on the same transcript.

So when a calculator has to turn a letter back into a single number, it is making a choice, not reading a fact. This one uses the middle of the band: 88.5% for a B plus, because the band runs 87 to 89.99. That is a reasonable convention and it is still a convention.

The place it strains most is F. An F covers everything below 60, so its middle sits near 30%, and nobody thinks a failing paper is automatically a 30. A failing grade’s real number depends entirely on how far below the line the work fell, and the letter has thrown that information away. If you are averaging a transcript with an F in it and the exact result matters, go back to the original percentages.

How to average letter grades

Averaging letters takes three steps: turn each letter into a number, take the average, turn the answer back into a letter. The Average letters tab runs all three for you, which is the part people are after when they search for a letter grade average calculator. The middle step is where the argument is, because whether you weight the courses changes the answer.

Take two college courses. An A in a one-credit seminar, and a C in a four-credit core course.

Counting them equally, an A is 95 and a C is 75, so the average is 85, which is a B.

Counting them by credits, the C is carrying four times the load: (95 × 1 + 75 × 4) ÷ 5 = 79, which is a C plus.

Same two grades. Two different letters. Neither calculation is wrong, they are answers to different questions, and a transcript almost always asks the second one. That is why Weight by credits is ticked when the tool loads, and why the calculator tells you what the unweighted answer would have been so you can see the gap rather than guess at it.

If every course really is worth the same, untick the box and the tool takes a plain average instead. That is the honest case for a set of quiz grades or a handful of assignments in one class, where no weighting exists to apply.

Your school’s scale is probably not this one

There is no national authority setting letter grades in the United States. Each institution writes its own, and they disagree more than most people expect. Two real examples, both from their own published sources.

Calculator.net, one of the most used calculators on the internet, runs a thirteen grade scale where A+ is worth 4.3 and a D- is worth 0.7. Its own page admits the problem: grading systems differ on what counts as an A or a B, and some do not include grades like an A+ or a B- at all.

UNC Chapel Hill proves the point. Its published undergraduate scale is A 4.0, A- 3.7, B+ 3.3, B 3.0, B- 2.7, C+ 2.3, C 2.0, C- 1.7, D+ 1.3, D 1.0, F 0.0. Read that again: there is no A+ and no D-. The rule is that pluses and minuses go on B and C, a minus can go on an A, and a plus can go on a D. Eleven grades, not thirteen.

Treat any grading scale you find online, including this one, as a starting point rather than an answer. Your handbook or registrar decides where the cutoffs sit and which letters exist, and they are the only source that counts for your transcript.

The percentage cutoffs move too. On a ten point scale a 70 is a C minus. On a seven point scale, where a C starts at 77, that identical 70 is a D. Districts sit on both sides of this, and it varies inside a single state: one high school grants the A at 90, another holds it until 94. Nothing about the work changed. The line did. The grade calculator high school tool works on whichever cutoffs your district uses.

All of which is why the scale on this page is editable. Untick the letters your school does not award, move the cutoffs to match your handbook, and the conversions and averages follow.

Letter grades and GPA points

Every letter carries a points value, and those points are what a grade point average is built from. This page starts A+ at 4.0, the same as an A. Schools genuinely disagree about that one letter, so the points column in the scale editor is yours to change. For the full letter, percentage and points table on three published scales that disagree with each other, and for conversions running in either direction, use the full conversion chart.

What this page will not do is calculate a full GPA across a transcript. Averaging letters within one set of courses is a different job from a semester or cumulative GPA with quality points and credit totals, and running them together is how people end up with a number they cannot reconcile against their own record.

Doing it in a spreadsheet

If you would rather keep the whole thing in a sheet, one formula does the conversion. This works in Excel and in Google Sheets, with the score in cell A2:

Change the numbers to match your own cutoffs and the letters follow. On older versions of Excel without IFS, a VLOOKUP against a two column table of cutoffs and letters, with the last argument set to TRUE, does the same job.

Averaging is the harder half, because you cannot average text. Convert each letter to its number first, average the numbers, then convert that result back with the same formula. That is the same three step process the tool runs, which is worth knowing if you ever need to show your working.

Percent to letter grade table

The percentage to letter grade conversion this page starts with, in both common forms. The tool lets you change any of it.

Schools run other scales entirely, so check yours before anything important rests on the answer. A 60 is the pass mark on this scale, but courses that count toward a major can demand a C or better, and that threshold has nothing to do with the letter cutoffs above it.

Related calculators

Letters usually come from somewhere. If the score you are converting is a test result, our test grade calculator turns questions and misses into a percentage first, and the letter follows from the scale you set here.

The scale itself is a choice, and not every school makes the same one. You can see the grading scale behind the letters, with the ten-point and seven-point versions side by side and what each does to the same score.

If you want the answer for one number rather than the scale behind it, every percentage from 100 down to 60 is listed out with its letter on two scales.